This session highlights advances in the development and application of land data assimilation systems (LDAS), which merge ground- or satellite-based observations with estimates from land surface models. Contributions may include studies that evaluate or refine land DA methods, and/or assess the impact of the assimilation on the quality of LDAS products.  These LDAS products may focus on the simulation of the land surface itself, or dependent processes, and could include simulation of surface hydrology, the atmosphere, drought, agriculture, and/or water resources.  Contributions focussed on transition of research to operations are particularly encouraged, as are studies that explore assimilation of novel and/or multiple observation types.